How much does science play into your love life? According to recent studies, it may be much more influential than you think. An important part of the human immune system involves Major Histocompatibility Complex (MHC) molecules, which are antigens that coat the cells in the human body. The diversity of these MHC molecules in the body determines the effectiveness of the immune system, but it seems to have other implications as well. Would you believe that it could influence who you crush on, or even more, who you marry?

Picture from here.

There is evidence that the diversity of MHC molecules in individuals influences mating choice in animals and humans. Natural sexual selection occurs so that humans are attracted to those with dissimilar MHC molecules, which allows them to produce offspring with greater biological diversity, and therefore, a greater chance of survival. So how does this natural law of attraction work? You may be surprised to know that body odor—yes, that rank stank that you always try to cover up—is the key.